Core box vent



D. E. ARNT CORE BOX VENT Nov. 2, 1965 Filed Jan. 3, 1963 1 m I I w F/G. 10 INVESTOR DAV/D E. ARNT FIG. 6

United States Patent O 3,214,803 CORE BOX VENT David E. Amt, Hilisdale, Mich., assignor to Hillsdale Tool and Manufacturing Company, Hillsdale, Mich., a corporation of Michigan Filed Jan. 3, 1963, Ser. No. 249,277 9 Claims. (CI. 2213) The invention pertains to the foundry and molding arts and particularly relates to a core box vent construction such as used in the formation of mold cores.

It is common practice to mold cores by blowing a mixture of the core material, usually moist sand and a binding agent, into the interior of a core box or core mold. To insure that the core material completely fills the core box and to prevent the formation of voids due to entrapped air, it is common practice to provide the core box with a plurality of vents. Such vents permit the escape of the air within the core box during injection of the core material, yet prevent the escape of the core material itself.

One of the basic problems attendant with core box vents lies in their tendency to clog due to the accumulation of the core material in the vent openings of the core box vent and thereby affect the efficiency of the vent. Also, as it is very difiicul-t to prevent the escape of the smaller particles and dust of the core material through the vent, the core box vent is subjected to severe abrasive conditions and wears rather rapidly, necessitating frequent replacement.

It is an object of the invention to provide a core box vent of economical manufacture which may be manufactured by stamping and forming apparatus and processes at a low cost.

Another object of the invention is to provide a core box vent of sheet metal construction which is self-cleaning and resists abrasive wear.

A further object of the invention is to provide a core box vent forming a substantially annular vent opening wherein the dimensions of the vent opening are consistently maintained during manufacture of the vent, and during the use thereof.

These and other objects of the invention arising from the details and relationships of the components of embodiments thereof will be apparent from the following description and accompanying drawings wherein:

FIG. 1 is an elevational, sectional, schematic view of a core box associated with the filling apparatus during the process of the filling of the core box,

FIG. 2 is an enlarged elevational, sectional, detail view of a core box vent, in accord with the invent-ion, as located within the wall of the core box,

FIG. 3 is an enlarged elevational, front view of a core box vent in accord with the invention,

FIG. 4 is a view of a core box vent blank, in accord with the invention, prior to the shaping thereof by bend- FIG. 5 is an end elevational view of the blank of FIG. 4 as taken from the right side thereof,

FIG. 6 is an elevational view of the core box vent during forming wherein the body portion has been formed, and prior to bending the head into position,

FIG. 7 is an elevational view of the fully formed core box vent after bending the head into place,

FIGS. 8 and 10 are views of other embodiments of core box vent blanks prior to the forming thereof, and

FIGS. 9 and 11 are front views of the core box vents formed from the blanks of FIGS. 8 and 10, respectively.

FIG. 1 illustrates, in a schematic manner, a typical relationship between a core box 10 and core box filling apparatus 12 during the filling of the core box to form the desired core. The core box filling apparatus 12 in- 'ice cludes a receptable 14 in which the core material 16 is received. The core material usually consists of moist sand, or the like, and a binding agent. An orifice 18 is formed in the bottom of the receptacle 14, and compressed air is introduced into the receptacle to force the core material through the orifice 18 into a core box 10 located therebelow. The core box 10 includes side walls 20 wherein the side and end walls thereof define the desired configuration of the core. Openings 22 are defined in the core box side walls of a cylindrical configuration for closely receiving the core box vents 24.

The relationship of the core box vent 24 to the core box side walls 20 will be readily appreciated from FIG. 2. The core box vent includes an annular body portion 26 of a cylindrical configuration which is closely received Wthin the cylindrical box openings 22. The axial length of the body portion 26 usually will be substantially equal to the thickness of the side Walls 20. The end of the body portion 26 disposed adjacent the interior of the core box is substantially enclosed by a head 28 having an outer surface 30 substantially aligned with the edge 32 of the body portion and the inner surface of the side walls 20. Thus, it will be appreciated that the core box vent 24 does not interfere with the configuration of the core box or affect the shape of the core to be formed thereby.

The front appearance of a core box vent 14, in accord with the invention, will be appreciated from FIG. 3. The front appearance is that from the interior of the core box. As previously mentioned, the head 28 substantially encloses the end of the body portion 26 adjacent the interior of the core box, and this head is of a circular configuration having a diameter slightly less than the inner diameter of the body portion. In that the head diameter is less than the inner diameter of the body member, and as the head is received within the axial dimensions of the body member, a substantially annular vent opening 34 will be defined between the periphery of the head and the inner surface of the body portion 26.

The annular configuration of the vent opening 34 is interrupted at three locations. One of these locations is due to the hinge portion 36 which afiixes the head 28 to the body portion 26. The other two locations of interruption of the vent opening are due to the locating prm jections or tongues 38 defined upon the head and radially extending from the periphery thereof.

The projections 38 include an enlarged portion defining shoulders 40 on each side of the projection. The shoulders 40 radially extend beyond the outer peripheral edge 42 of the head a distance equal to the desired radial dimension of the vent opening 34. The projections 38 also include a portion 44 of lesser circumferential dimension than the projection portion defining shoulders 40. The portion 44 is adapted to be received within a recess 46 defined in the body portion 26 which intersects the edge 32 thereof.

With reference to FIGS. 3 and 7, it will be appreciated that in the assembled relation the shoulders 40 engage the inner surface of the body portion adjacent the asso ciated recess 46, and that the projection portions 44 will be received within the recesses 46. Thus, the hinge portion 36 and the shoulders 40 will insure that the radial dimension of the vent opening 34 throughout its circumference will be uniformly maintained, and uniform vent flow characteristics may be maintained with little or no loss of core material during filling 0f the core box.

It will be appreciated from FIG. 2 through 6 that the peripheral surface 48 of the head 28 is conical and con verges away from the interior of the core box. In a similar manner the recesses 46 are provided with a tapered surface 50. The tapered surfaces 50 of the recesses also converge away from the interior of the core box.

An advantage of employing the conical surface 48 and the tapered surfaces 50 lies in the improved self-cleaning characteristics such constructions provide. The core material 16 is forced into the core box I l)v under relatively high air pressure, and the escape of the air through the core box vent openings 34 will cause the head 28 to slightly vibrate relative to the body portion 26. Such vibration isdue to the fact that the hinge portion 36 constitutes a resilient mounting of the head relative to the body portion, and as the projections 38 are not rigidly affixed within the recesses 46, but are merely located therein, such vibration may occur in the axial direction of the body portion without adversely affecting the dimensional characteristics of the vent opening. The vibration of the head 28, though of slight magnitude, tends to permit very small core material particles and dust which have lodged within the vent opening 34 to work their way therethrough, and the conical surfaces 48 and 50 provide clearance for such a self-cleaning action. Also, the use of the conical surfaces provides an efiicient flow path for the escaping air.

As previously mentioned, the core box vent in accord with the invention may be produced from sheet metal by a stamping operation. FIG 4 illustrates the form of the stamped blank from which the vent is constructed. The surfaces 48 and 50 may be formed by a second operation after the blank has been stamped from the sheet stock, or may be formed by a stamping operation if the necessary die structure for forming these surfaces by stamping is available. As will be appreciated from FIG. 4, the body portion 26 will be of a substantially rectangular configuration being defined at the ends by edges 52 and including a linear edge which constitutes the inner edge 32 in which the recesses 46 are formed. The circular head 28 is integrally attached to the body portion by the neck or hinge portion 36 which extends perpendicularly from the edge 32.

In the formation of the core box vent from the blank of FIG. 4, the body portion 26 is formed into an annular, cylindrical configuration wherein the ends 52 will be in an opposed and substantially abutting relationship, as shown in FIG. 3. Thereupon, the head 28 is bent from the position of FIG. 6 to that of FIG. 7 wherein the head is located within the end of the body portion adjacent the edge 32 by bending the hingle portion 36 adjacent the edge 32. These two bending operations complete the formation of the core box vent from the planar blank form of FIG. 4. It will be appreciated that the abovedescribed core box vent and the method of construction thereof provides a very economical vent for fulfilling the purposes and objects of the invention. If desired, the core box vent, in accord with the invention, may be hardened by conventional heat-treating processes to resist the abrasive action of the core material.

FIGS. 8 and 9 are directed to another embodiment of the invention of a simplified construction. In the embodiment of FIG. 8 the core box ventblank includes the body portion 54 having a linear, longitudinal edge 56 and end edges 58. The head 60 is of a circular configuration having a peripheral conical surface 62 defined thereon, and is attached to the body portion by the hinge portion 64. The core box embodiment of FIGS. 8 and 9 is formed in the same manner as the previously described embodiment except that as no radially extending tongues or projections are defined upon the periphery of the head, the only association between the head 60 and the body portion 54 will occur at the hinge portion 64. Thus, the vent opening 66, FIG. 9, will be interrupted only at the hinge portion 64. In that the hinge portion 64 will resiliently support the head relative to the body portion, the self-cleaning action, previously described, will also be present in this embodiment. However, in that tongues and projections are not employed with this embodiment, the maintenance of the uniform radial dimension of the vent opening will be more diflicult and no means, other than the hinge portion itself, are provided for preventing the axial forces applied upon the head during filling, from possibly deforming the head into the body portion. It will be appreciated that in the embodiment of FIGS. 1 through 7 that the engagement of the projection portions 44 with the edge of surfaces 50 nearest the edge 32 will prevent the head 28 from being deformed or bent into the body portion 26 due to air pressure within the core box during filling, and this structural feature is not included in the simplified embodiment of FIGS. 8 and 9. However, the embodirnent of FIGS. 8 and 9 can be employed in installations wherein lower core box filling pressures are employed and the maintenance of accurate vent opening dimensions is not critical.

The embodiment of FIGS. 10 and 11 employs a combination of the features of the previously described embodiments. This embodiment of the invention employs a body portion 68 having a longitudinal edge 70 and end edges 72. The edge 70 is slightly recessed at 74 adjacent the hinge portion 76, and the head 78 depends from the hinge portion.

The end edges 72 are notched at 80 which are provided with tapered surfaces 81 which function in the manner of the surfaces 50, as will be later apparent.

A single projection 82 is defined on head 78 diametrically related to hinge portion 76, and is formed with shoulders 84 and a reduced portion 86 in a manner similar to the projections 38. Upon the body portion 68 being formed in an annular configuration wherein the end edges 72 are in substantial abutting relationship, the notches 80 will define a recess for receiving the projection reduced portion 86. Thus, the notches 80 will provide a recess for supporting the projection 82, in the manner of the projections 38 and recess 46, and accurately relate the head 78 to the body portion 68, and prevent the head from being deformed into the body portion by air pressure. The head is provided with a conical surface 88 which aids in the self-cleaning action of the vent during the slight vibration of the head, and the surfaces 81 also function to maintain the vent free of sand and core material.

The recessed edge at 74 aids in providing a uniform appearance of the hinge portion after the bending thereof, and it will be noted from FIG. 11 that, as the edges of the notches 80 substantially engage the radial sides of the reduced portion 86, lateral deflection of the head 78 relative to the body portion will be prevented.

If the configuration of the core box is such that no planar surfaces are present, the vent heads of the various embodiments may be formed into a concave or convex configuration to conform to the core without departing from the spirit of the invention. It will be appreciated that various modifications to the invention may be apparent to those skilled in the art without departing from the spirit and scope thereof, and it is intended that the invention be defined only by the scope of the following claims.

I claim:

1. A core box vent formed from an integral blank of sheet material comprising, in combination,

(a) an annular body portion having an edge transversely disposed to the axis of said body portion and defining an end thereof, said edge adapted to be located adjacent a mold cavity,

(b) a head resiliently connected to said body portion at said edge thereof, said head having a general peripheral configuration similar to the annular configuration of said body portion and disposed adja cent said body portion edge,

(c) said head dimensions being so related to said body portion whereby a vent opening is defined between the periphery of said head and said body portion, and

(d) said body portion including an open end oppositely disposed relative to said edge.

2. In a core box vent as in claim 1 wherein (a) said head is located within said body portion, said head having an outer surface defined thereon and the outermost portion of said surface substantially axially aligning with said edge.

3. In a core box vent as in claim 2, wherein (a) the periphery of said head is relieved in an inwardly direction with respect to said body portion whereby the width of said vent opening increases in the axial direction within the axial length of said head in the direction of air flow through said vent.

4. A core box vent constructed from an integral stamping of sheet material comprising, in combination,

(a) a body portion having a longitudinal edge formed into an annular configuration wherein said edge con stitutes an end of the annular body member form,

(b) a deformable hinge portion extending from said longitudinal edge,

(e) a head having a peripheral configuration similar to the annular configuration of said body portion,

((1) said deformable hinge portion interconnecting a peripheral portion of said head to said body portion longitudinal edge,

(e) said hinge portion being bent to extend in a radial direction with respect to said annular body portion configuration wherein the periphery of said head portion is disposed adjacent the end of said body portion defined by said longitudinal edge,

(t) the transverse dimension of said head being less than the transverse dimension of said annular body portion wherein a substantially annular vent opening is defined between the periphery of said head and body portion, and

(g) said body portion including an open end oppositely disposed relative to said edge.

5. As an article of manufacture, an integral stamped blank of sheet material adapted to be formed into a core box vent,

(a) a body portion having a longitudintal edge,

(b) a neck portion of deformable character transversely extending from said longitudinal edge, and

(c) a generally circular head member attached to and depending from said hinge portion, said head member having a peripheral circumference slightly less than the length of said longitudinal edge.

6. A core box vent comprising, in combination,

(a) an annular body portion having an end edge de fined thereon,

(b) a head having a general peripheral configuration similar to the internal configuration of said body portion,

(c) a resilient element connecting a peripheral portion of said head to said end edge,

(d) said head being substantially coaxially received Within said body portion and being of lesser transverse dimension than the internal transverse dimension of said body member whereby the periphery of said head and said body portion define an annular vent opening, and

(c) cooperating locating means defined upon said head and body portion locating said head relative to said body portion.

7. In a core box vent as in claim 9, wherein (a) said locating means include a radially extending projection defined upon said head, and

(b) a recess defined in said end edge receiving said projection.

8. In a core box vent as in claim 7, wherein (a) a shoulder is defined on said head radially spaced a greater distance from the axis of said body portion and head than the head periphery,

(b) said shoulder engaging the inner surface of said body portion to maintain said head coaxial with said body portion and maintain a predetermined vent opening dimension.

9. The method of forming a core box vent from a planar stamped blank of sheet material comprising the steps of (a) stamping a blank from sheet material having a body portion having an edge and a head portion connected to said edge by a hinge portion,

(b) forming said body portion into an annular configuration by bending wherein said edge constitutes an end of the annular configuration transversely disposed to the axial longitudinal length thereof, and

(c) bending said hinge portion substantially perpendicular to the axis of said annular body portion wherein said head portion is received within said body portion adjacent the edge thereof.

References Cited by the Examiner UNITED STATES PATENTS 889,115 5/08 Frere et al. 22-184 1,446,446 2/23 Bellon 22-184 2,126,097 8/38 Demmler 22-13 2,482,321 9/49 Copeland et al. 22-13 2,914,821 12/59 Yahnka 22-13 3,025,818 3/62 Lyon 113-116 3,066,631 12/62 Geary 113-116 MARCUS U. LYONS, Primary Examiner.

V. BRINDISI, Examiner, 

1. A CORE BOX VENT FORMED FROM AN INTEGRAL BLANK OF SHEET MATERIAL COMPRISING, IN COMBINATION, (A) AN ANMNULAR BODY PORTION HAVING AN EDGE TRANSVERSELY DISPOSED TO THE AXIS OF SAID BODY PORTION AND DEFINING AN END THEREOF, SAID EDGE ADAPTED TO BE LOCATED ADJACENT A MOLD CAVITY, (B) A HEAD RESILIENTLY CONNECTED TO SAID BODY PORTION AT SAID EDGE THEREOF, SAID HEAD HAVING A GENERAL PERIPHERAL CONFIGURATION SIMILAR TO THE ANNULAR CONFIGURATION OF SAID BODY PORTION AND DISPOSED ADJACENT SAID BODY PORTION EDGE, (C) SAID HEAD DIMENSIONS BEING SO RELATED TO SAID BODY PORTION WHEREBY A VENT OPENING IS DEFINED BETWEEN THE PERIPHERY OF SAID HEAD AND SAID BODY PORTION, AND (D) SAID BODY PORTION INCLUDING AN OPEN END OPPOSITELY DISPOSED RELARIVE TO SAID EDGE.
 9. THE METHOD OF FORMING A CORE BOX VENT FROM A PLANAR STAMPED BLANK OF SHEET MATERIAL COMPRISING THE STEPS OF 